The present invention relates to an information processing apparatus, an information recording medium, an information processing method, and a computer program. And more particularly to an information processing apparatus, an information recording medium, an information processing method, and a computer program for realizing the storage of various contents that require contents usage management and the usage management of contents for each of finely segmentalized data units.
Various software data including audio data such as music data, image data such as movie data, game programs, various application programs (hereinafter referred to as “contents”) can be stored as digital data on various recording mediums, e.g., Blu-ray discs using blue laser, DVDs (Digital Versatile Discs), MDs (Mini Discs), and CDs (Compact Discs). In particular, Blu-ray discs are discs capable of storing data in highly packed density, and can record a large amount of video contents or the like as data of high image quality.
Digital contents are stored in such various information recording mediums and provided to users. Users play and use the contents recorded in such information recording mediums on their playback units such as PCs (Personal Computers), disc players, etc.
Many contents including music data, image data, etc. are generally protected under distribution rights owned by their producers or sellers. It is customary to pose certain limitations on the distribution of those contents, i.e., to allow only normal users to use contents and inhibit unauthorized duplication, etc.
Digital recording devices and recording mediums are capable of repeatedly recording and reproducing digital contents without deteriorating image and audio data. They tend to give rise to such problems as the delivery of unauthorized copy contents via the Internet, the distribution of pirate discs such as CD-R with copied contents, and the widespread use of copy contents stored in the hard discs of PCs or the like.
Large-capacity recording mediums such as DVDs or recording mediums using blue laser that has been developed in recent years allow a large amount of data, e.g., data of one or several movies, as digital information on a single medium. In view of the ability to record video information as digital information, it is of growing importance to prevent unauthorized copying to protect copyright holders. Recent years have seen digital recording devices and recording medium that incorporate various techniques of preventing digital data from being copied unlawfully.
For example, DVD players employ a content scrambling system. According to the content scrambling system, video data and audio data are encrypted and recorded on a DVD-ROM (Read-Only Memory), and a key for decrypting the encrypted data is given to a licensed DVD player. The license is given to those DVD players that are designed to comply with certain operation rules against unauthorized copying. The licensed DVD player uses the given key to decrypt the encrypted data recorded on the DVD-ROM for thereby reproducing images and sounds from the DVD-ROM.
An unlicensed DVD player, on the other hand, is incapable of decrypting the encrypted data recorded on the DVD-ROM as it does not have the key to decrypt the encrypted data. According to the content scrambling system, therefore, any DVD players that do not meet the requirements for the license cannot play back the DVD-ROM with recorded digital data, thus preventing unauthorized duplication.
With the recent widespread use of data communication networks, so-called home networks are beginning to find use at home for networking home electric appliances, computers, and other peripherals to allow communications therebetween. Home networks give users convenience and comfort by allowing networked devices to communicate with each other thereby to share data processing functions of the devices and also to send and receive contents between the devices, and are expected to find increasing use in the future.
As such networked environments become more popular, there are more opportunities for the contents stored in information recording mediums to be accessed and used by devices that are connected to home networks. The above conventional unauthorized copy prevention system is based on the concept that the playback of contents is allowed on only one licensed player. Therefore, no sufficient consideration has been given to the situation where a networked device loaded with a recording medium, e.g., a home server or a player, is accessed by another networked device, e.g., a PC, a TV set, or the like, to play back the contents through the network.
Heretofore, since it has been the mainstream to use one content stored on a recording medium with a single player, it has been sufficient for performing the usage management of contents by establishing contents access rights such as a license for the contents or the player. At present, however, information recording mediums of larger capacity and home-use digital and networked devices in wider use require contents usage management arrangements different from those in the past. Specifically, there are demands, to be described below, for new contents usage management arrangements.
(1) The realization of arrangements for recording a plurality of contents on a recording medium and performing different usage management for each content.
(2) The realization of contents usage management arrangements for allowing contents to be used in a certain network such as a home network, or specifically allowing contents to be played back by a network-connected device and to be copied by a home server.
(3) The realization of arrangements for distributing information required to play back contents via a network, e.g., a key applied to decrypt contents, safety to a particular user.
It has been desired to realize the arrangements described above in (1) through (3).